850 Thermoquad worth the effort?

An acquaintance has an 850 Thermoquad Competition Series #4846 that is still new in the box that he'll let me have for cheap. He has no use for it and isn't into selling stuff on the net. Would this carb be worth the effort to try on my 70 340? I know that rebuild kits are available but the tuning parts seem to be hard to come by? My understanding is that the TQ can be a great carb but tuning is a bit different than a Holley. Car currently has a Holley 650 DP on it. Seems OK after I rebuilt it but I've only got 35 miles on it since I got it running and the trans is slipping so I haven't been able to give it a good workout. Currently has J-heads, LD4B intake and as far as I can tell a relatively stock cam. Will be getting new heads (new TF, W2, or ??), RPM air gap, and as hot a solid lifter cam as I can comfortably run on the street. I have the room under the hood to run a 1" adapter.